CERBERUS by Jonathan Stafford
Huge black Rottweiler, twice the size of a wooly mammoth, with three heads. The hound of Hades who guards the entrance to the Underworld and prevents the dead from leaving.
. . .
The name "Cerberus" is a Latinised version of the Greek Kerberos, which may be related to the Sanskrit word सर्वरा "sarvarā", used as an epithet of one of the dogs of Yama, from a Proto-Indo-European word *ḱerberos, meaning "spotted" (This etymology suffers from the fact that it includes a reconstructed *b, which is extremely rare in Proto-Indo-European. Yet according to Pokorny it is well distributed, with additional apparent cognates in Slavic, British and Lithuanian). The use of a dog is uncertain, although mythologists have speculated that the association was first made in the city of Trikarenos in Phliasia.
Cerberus is said to be the sibling of the Lernaean Hydra, the Nemean Lion, the Sphinx, the Ladon, and the Chimera.
"Cerberus" is generally pronounced in English with a soft C as in cell, even though the ancient pronunciation, in both Greek and Latin was with a hard C as in cat.
Cerberus was the offspring of Echidna, a hybrid half-woman and half-serpent, and Typhon, a fire-breathing giant whom even the Olympian gods feared. Its brother is Orthrus, always depicted as a two-headed hellhound. The common depiction of Cerberus in Greek mythology and art is as having three heads, a mane of live serpents (similar to Medusa's hair) and a snake's tail. In most works the three-heads each respectively see and represent the past, the present, and the future, while other sources suggest the heads represent birth, youth, and old age. Each of Cerberus' heads is said to have an appetite only for live meat and thus allow the spirits of the dead to freely enter the underworld, but allow none to leave. Cerberus was always employed as Hades' loyal watchdog, and guarded the gates that granted access and exit to the underworld (also called Hades).
Source(s): Percy Jackson and the Olympians - The Ultimate Guide ;;Wikipedia